A. Field of the Invention
The present invention relates to a cryogenic applicator and, more particularly, to a cryogenic applicator for rejuvenating skin and a method for using the applicator.
B. Description of the Prior Art
Liquid nitrogen, and/or other biocompatible non-toxic cryogenic liquids, all herein sometimes referred to as “cryogenic liquids” is frequently used at offices of physicians in removal of warts, lesions, sun damage and/or the like from a person's skin. For example a method used for removing a wart is to apply liquid nitrogen thereto for a substantial length of time, usually a matter of seconds. The liquid nitrogen has a boiling temperature of approximately −335° F.
Although liquid nitrogen is here mentioned, it will be understood that other suitable biocompatible non-toxic cryogenic liquids could be substituted therefor and the very cold temperature used in the treatment could be different and might vary. In treating the wart, the nitrogen “burns” by freezing the wart.
Numerous innovations for skin rejuvenation have been provided in the prior art that will be described below. Even though each of these innovations may be suitable for a specific purpose to which it is addressed, said innovations all differ in structure and/or technique and/or objective from that of the present invention.
(1) U.S. Pat. No. 4,074,717 to Schulze et al.
U.S. Pat. No. 4,074,717, which issued to Schulze et al. on Feb. 21, 1978, teaches a cryogenic probe, its method of charging, and its method of use. The probe includes a barrel having a plunger mechanism movably mounted therein and a valve on the lower end thereof. The valve normally closes the lower end of the barrel, but the plunger may be moved relative to the barrel to permit cryogenic liquid, such as liquid nitrogen, to by-pass the valve and move upwardly into the interior of the barrel. The valve has a tip portion at the lower end thereof. The barrel is removably positioned in a guard, so that the tip portion extends outwardly through the bottom of the guard whereby the upper end of the plunger is exposed above the guard. The tip portion has a lower end portion which is extremely thin, so that the cryogenic liquid will be positioned closely adjacent the skin, but not in actual contact therewith when the tip portion is placed into contact with the patient's skin.
(2) U.S. Pat. No. 5,330,745 to McDow.
U.S. Pat. No. 5,330,745 issued to McDow on Jul. 19, 1994 and it teaches a method for cryogenically treating a skin lesion employing a hollow fluid retaining device for retaining cryogenic refrigerant in a liquid pool, and then contacting the area of the skin lesion at a temperature and for a time, so that permanent, irreversible rupture of the cellular membrane of the lesion cells occurs.
(3) U.S. Pat. No. 6,350,276 to Knowlton.
U.S. Pat. No. 6,350,276 issued to Knowlton on Feb. 26, 2002 and it teaches a fluid delivery apparatus for introducing a fluid cooling media to a skin surface, including a template with a skin interface surface. An energy delivery device is coupled to the template. A fluid cooling media introduction member is coupled to the template. Resources controllably deliver energy from the energy delivery device to the skin surface. In a related embodiment, the resources are configured to controllably deliver the flowable cooling media to the introduction member. In another embodiment, a sensor is coupled to the resources and to the skin surface.
(4) U.S. Pat. No. 6,726,693 to Weber et al.
U.S. Pat. No. 6,726,693 issued to Weber et al. on Apr. 27, 2004 and it teaches tissue resurfacing accomplished by propelling biocompatible, non-toxic materials at the tissue with sufficient velocity to cause destruction or loosening of tissues to a desired depth. The biocompatible materials are generated by abrading a solid frozen unit and propelling the abraded material onto the surface of the skin or tissue to be treated. A vacuum line near the delivery tip may be used to remove excess materials or reaction by-products building up on the surface of the skin. The treatment system generally includes a control unit, a handheld particle generator, and a cable connecting the control unit to the particle generator. The control unit can include user controls to select particle temperature, particle flux, particle velocity, and vacuum. The handheld particle generator contains a mechanism to push the frozen biocompatible material against a rotating grinding wheel producing the small particles being propelled against tissue being treated.
(5) U.S. Pat. No. 6,749,624 to Knowlton.
U.S. Pat. No. 6,749,624 issued to Knowlton on Jun. 15, 2004 and it teaches a fluid delivery apparatus for introducing a fluid cooling media to a skin surface, including a template with a skin interface surface. An energy delivery device is coupled to the template. A fluid cooling media introduction member is coupled to the template. Resources controllably deliver energy from the energy delivery device to the skin surface. In a related embodiment, the resources are configured to controllably deliver the flowable cooling media to the introduction member. In another embodiment, a sensor is coupled to the resources and to the skin surface.
(6) U.S. Pat. No. 6,764,493 to Weber et al.
U.S. Pat. No. 6,764,493 issued to Weber et al. on Jul. 20, 2004 teaches biocompatible materials being propelled at the skin with sufficient velocity to cause desired resurfacing of tissue to the desired penetration depth. The materials, such as dry ice or water ice, are harmonious with the human body and thus eliminate foreign body reactions. Various materials may be used in combination, including local anesthetics and vasoconstrictors in solid or liquid form. The biocompatible solid or liquid particles are suspended in a cold carrier fluid and are propelled through an insulated delivery system to the surface of the skin. The treatment of diseased skin lesions may be accomplished by its use as a drug delivery system.
It is apparent that numerous innovations for skin treatments have been provided in the prior art. Even though these innovations each may be suitable for a specific purpose to which it is addressed, the innovations would not be suitable, either individually or collectively, for the purposes of the present invention as hereafter described.